/**
 *	@file    sha256.c
 *	@version 8e6f0e1 (HEAD -> master)
 *
 *	SHA256 hash implementation.
 */
/*
 *	Copyright (c) 2013-2016 INSIDE Secure Corporation
 *	Copyright (c) PeerSec Networks, 2002-2011
 *	All Rights Reserved
 *
 *	The latest version of this code is available at http://www.matrixssl.org
 *
 *	This software is open source; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	This General Public License does NOT permit incorporating this software
 *	into proprietary programs.  If you are unable to comply with the GPL, a
 *	commercial license for this software may be purchased from INSIDE at
 *	http://www.insidesecure.com/
 *
 *	This program is distributed in WITHOUT ANY WARRANTY; without even the
 *	implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *	See the GNU General Public License for more details.
 *
 *	You should have received a copy of the GNU General Public License
 *	along with this program; if not, write to the Free Software
 *	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *	http://www.gnu.org/copyleft/gpl.html
 */
/******************************************************************************/

#include "../cryptoApi.h"

#ifdef USE_MATRIX_SHA256

/******************************************************************************/

#ifndef PS_SHA256_IMPROVE_PERF_INCREASE_CODESIZE

/* The K array */
static const uint32_t K[64] = {
	0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL,
	0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL,
	0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL,
	0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
	0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL,
	0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL,
	0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL,
	0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
	0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL,
	0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL,
	0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL,
	0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
	0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL
};
#endif /* PS_SHA256_IMPROVE_PERF_INCREASE_CODESIZE */

/* Various logical functions */
#define Ch(x,y,z)			(z ^ (x & (y ^ z)))
#define Maj(x,y,z)			(((x | y) & z) | (x & y))
#define S(x, n)				ROR((x),(n))
#define R(x, n)				(((x)&0xFFFFFFFFUL)>>(n))
#define Sigma0(x)			(S(x, 2) ^ S(x, 13) ^ S(x, 22))
#define Sigma1(x)			(S(x, 6) ^ S(x, 11) ^ S(x, 25))
#define Gamma0(x)			(S(x, 7) ^ S(x, 18) ^ R(x, 3))
#define Gamma1(x)			(S(x, 17) ^ S(x, 19) ^ R(x, 10))

/*
	compress 512-bits
 */
#ifdef USE_BURN_STACK
static void _sha256_compress(psSha256_t *sha256, const unsigned char *buf)
#else
static void sha256_compress(psSha256_t *sha256, const unsigned char *buf)
#endif /* CLEAN_STACK */
{

	uint32 S[8], W[64], t0, t1;
#ifndef PS_SHA256_IMPROVE_PERF_INCREASE_CODESIZE
	uint32 t;
#endif /* PS_SHA256_IMPROVE_PERF_INCREASE_CODESIZE */
	int32 i;

	/* copy state into S */
	for (i = 0; i < 8; i++) {
		S[i] = sha256->state[i];
	}

	/* copy the state into 512-bits into W[0..15] */
	for (i = 0; i < 16; i++) {
		LOAD32H(W[i], buf + (4*i));
	}

	/* fill W[16..63] */
	for (i = 16; i < 64; i++) {
		W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];
	}

	/* Compress */
#ifndef PS_SHA256_IMPROVE_PERF_INCREASE_CODESIZE
#define RND(a,b,c,d,e,f,g,h,i)							\
	t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];	\
	t1 = Sigma0(a) + Maj(a, b, c);						\
	d += t0;											\
	h  = t0 + t1;

	for (i = 0; i < 64; ++i) {
		RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i);
		t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4];
		S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t;
	}
#else /* PS_SHA256_IMPROVE_PERF_INCREASE_CODESIZE */
#define RND(a,b,c,d,e,f,g,h,i,ki)						\
	t0 = h + Sigma1(e) + Ch(e, f, g) + ki + W[i];		\
	t1 = Sigma0(a) + Maj(a, b, c);						\
	d += t0;											\
	h  = t0 + t1;

	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],0,0x428a2f98);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],1,0x71374491);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],2,0xb5c0fbcf);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],3,0xe9b5dba5);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],4,0x3956c25b);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],5,0x59f111f1);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],6,0x923f82a4);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],7,0xab1c5ed5);
	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],8,0xd807aa98);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],9,0x12835b01);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],10,0x243185be);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],11,0x550c7dc3);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],12,0x72be5d74);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],13,0x80deb1fe);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],14,0x9bdc06a7);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],15,0xc19bf174);
	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],16,0xe49b69c1);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],17,0xefbe4786);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],18,0x0fc19dc6);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],19,0x240ca1cc);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],20,0x2de92c6f);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],21,0x4a7484aa);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],22,0x5cb0a9dc);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],23,0x76f988da);
	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],24,0x983e5152);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],25,0xa831c66d);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],26,0xb00327c8);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],27,0xbf597fc7);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],28,0xc6e00bf3);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],29,0xd5a79147);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],30,0x06ca6351);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],31,0x14292967);
	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],32,0x27b70a85);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],33,0x2e1b2138);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],34,0x4d2c6dfc);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],35,0x53380d13);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],36,0x650a7354);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],37,0x766a0abb);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],38,0x81c2c92e);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],39,0x92722c85);
	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],40,0xa2bfe8a1);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],41,0xa81a664b);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],42,0xc24b8b70);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],43,0xc76c51a3);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],44,0xd192e819);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],45,0xd6990624);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],46,0xf40e3585);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],47,0x106aa070);
	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],48,0x19a4c116);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],49,0x1e376c08);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],50,0x2748774c);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],51,0x34b0bcb5);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],52,0x391c0cb3);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],53,0x4ed8aa4a);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],54,0x5b9cca4f);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],55,0x682e6ff3);
	RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],56,0x748f82ee);
	RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],57,0x78a5636f);
	RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],58,0x84c87814);
	RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],59,0x8cc70208);
	RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],60,0x90befffa);
	RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],61,0xa4506ceb);
	RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],62,0xbef9a3f7);
	RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],63,0xc67178f2);

#undef RND

#endif /* PS_SHA256_IMPROVE_PERF_INCREASE_CODESIZE */

	/* feedback */
	for (i = 0; i < 8; i++) {
		sha256->state[i] = sha256->state[i] + S[i];
	}

}

#ifdef USE_BURN_STACK
static void sha256_compress(psSha256_t *sha256, const unsigned char *buf)
{
	_sha256_compress(sha256, buf);
	psBurnStack(sizeof(uint32) * 74);
}
#endif /* USE_BURN_STACK */

/******************************************************************************/

int32_t psSha256Init(psSha256_t *sha256)
{
#ifdef CRYPTO_ASSERT
	psAssert(sha256 != NULL);
#endif
	sha256->curlen = 0;
	sha256->state[0] = 0x6A09E667UL;
	sha256->state[1] = 0xBB67AE85UL;
	sha256->state[2] = 0x3C6EF372UL;
	sha256->state[3] = 0xA54FF53AUL;
	sha256->state[4] = 0x510E527FUL;
	sha256->state[5] = 0x9B05688CUL;
	sha256->state[6] = 0x1F83D9ABUL;
	sha256->state[7] = 0x5BE0CD19UL;
#ifdef HAVE_NATIVE_INT64
	sha256->length = 0;
#else
	sha256->lengthHi = 0;
	sha256->lengthLo = 0;
#endif /* HAVE_NATIVE_INT64 */
	return PS_SUCCESS;
}

/******************************************************************************/

void psSha256Update(psSha256_t *sha256, const unsigned char *buf, uint32_t len)
{
	uint32 n;

#ifdef CRYPTO_ASSERT
	psAssert(sha256 != NULL);
	psAssert(buf != NULL);
#endif

	while (len > 0) {
		if (sha256->curlen == 0 && len >= 64) {
			sha256_compress(sha256, (unsigned char *)buf);
#ifdef HAVE_NATIVE_INT64
			sha256->length += 512;
#else
			n = (sha256->lengthLo + 512) & 0xFFFFFFFFL;
			if (n < sha256->lengthLo) {
				sha256->lengthHi++;
			}
			sha256->lengthLo = n;
#endif /* HAVE_NATIVE_INT64 */
			buf		+= 64;
			len		-= 64;
		} else {
			n = min(len, (64 - sha256->curlen));
			memcpy(sha256->buf + sha256->curlen, buf, (size_t)n);
			sha256->curlen	+= n;
			buf					+= n;
			len					-= n;

			if (sha256->curlen == 64) {
				sha256_compress (sha256, sha256->buf);
#ifdef HAVE_NATIVE_INT64
				sha256->length += 512;
#else
				n = (sha256->lengthLo + 512) & 0xFFFFFFFFL;
				if (n < sha256->lengthLo) {
					sha256->lengthHi++;
				}
				sha256->lengthLo = n;
#endif /* HAVE_NATIVE_INT64 */
				sha256->curlen	= 0;
			}
		}
	}
	return;
}

/******************************************************************************/

void psSha256Final(psSha256_t *sha256, unsigned char hash[SHA256_HASHLEN])
{
	int32 i;
#ifndef HAVE_NATIVE_INT64
	uint32	n;
#endif

#ifdef CRYPTO_ASSERT
	psAssert(sha256 != NULL);
	psAssert(hash != NULL);
	if (sha256->curlen >= sizeof(sha256->buf)) {
		psTraceCrypto("psSha256Final error\n");
		return;
	}
#endif

	/* increase the length of the message */
#ifdef HAVE_NATIVE_INT64
	sha256->length += sha256->curlen << 3;
#else
	n = (sha256->lengthLo + (sha256->curlen << 3)) & 0xFFFFFFFFL;
	if (n < sha256->lengthLo) {
		sha256->lengthHi++;
	}
	sha256->lengthHi += (sha256->curlen >> 29);
	sha256->lengthLo = n;
#endif /* HAVE_NATIVE_INT64 */

	/* append the '1' bit */
	sha256->buf[sha256->curlen++] = (unsigned char)0x80;

/*
	if the length is currently above 56 bytes we append zeros then compress.
	Then we can fall back to padding zeros and length encoding like normal.
*/
	if (sha256->curlen > 56) {
		while (sha256->curlen < 64) {
			sha256->buf[sha256->curlen++] = (unsigned char)0;
		}
		sha256_compress(sha256, sha256->buf);
		sha256->curlen = 0;
	}
	/* pad upto 56 bytes of zeroes */
	while (sha256->curlen < 56) {
		sha256->buf[sha256->curlen++] = (unsigned char)0;
	}

	/* store length */
#ifdef HAVE_NATIVE_INT64
	STORE64H(sha256->length, sha256->buf+56);
#else
	STORE32H(sha256->lengthHi, sha256->buf+56);
	STORE32H(sha256->lengthLo, sha256->buf+60);
#endif /* HAVE_NATIVE_INT64 */
	sha256_compress(sha256, sha256->buf);

	/* copy output */
	for (i = 0; i < 8; i++) {
		STORE32H(sha256->state[i], hash+(4*i));
	}
	memset(sha256, 0x0, sizeof(psSha256_t));
}

#ifdef USE_SHA224
/******************************************************************************/

void psSha224Init(psSha256_t *sha256)
{
#ifdef CRYPTO_ASSERT
	psAssert(sha256 != NULL);
#endif

	sha256->curlen = 0;
#ifdef HAVE_NATIVE_INT64
	sha256->length = 0;
#else
	sha256->lengthHi = 0;
	sha256->lengthLo = 0;
#endif /* HAVE_NATIVE_INT64 */
	sha256->state[0] = 0xc1059ed8UL;
	sha256->state[1] = 0x367cd507UL;
	sha256->state[2] = 0x3070dd17UL;
	sha256->state[3] = 0xf70e5939UL;
	sha256->state[4] = 0xffc00b31UL;
	sha256->state[5] = 0x68581511UL;
	sha256->state[6] = 0x64f98fa7UL;
	sha256->state[7] = 0xbefa4fa4UL;
}

/******************************************************************************/

void psSha224Update(psSha256_t *sha256, const unsigned char *buf, uint32 len)
{
	psSha256Update(sha256, buf, len);
}

/******************************************************************************/

void psSha224Final(psSha256_t *sha256, unsigned char out[SHA224_HASHLEN])
{
	unsigned char buf[SHA224_HASHLEN];

#ifdef CRYPTO_ASSERT
	psAssert(sha256 != NULL);
	psAssert(out != NULL);
#endif
	psSha256Final(sha256, buf);
	memcpy(out, buf, SHA224_HASH_SIZE);
#ifdef USE_BURN_STACK
	psBurnStack(sizeof(buf));
#endif
}
#endif /* USE_SHA224 */

#endif /* USE_MATRIX_SHA256 */

/******************************************************************************/

